Consistency and Repeatability in Brewing

I’ve been catching up on old episodes of The Brewing Network’s Brew Strong, and a recurring theme is consistency and repeatability. That got me thinking about my own process, so I decided to write this post and update my brew session template.

For anyone new to brewing who might come across this—don’t worry if your process looks different from mine. Very few systems are identical. For example, you may use a different mash thickness, and that’s perfectly fine. The key is to experiment and find what works best for your setup.

You also don’t need to rush out and buy more equipment to measure every possible variable. If you don’t have a sight glass or a pH meter, focus on what you can measure and document those things consistently from batch to batch. Even simple tools can be effective—for instance, if you’re using pH strips, you could take a photo under consistent lighting to compare results over time. If something seems off, your notes will give you a reliable reference point.

Brewing has countless variables that affect consistency, and even the pros struggle with this. Years ago, I did a Pro-Am Flanders Red with Uinta Brewing and saw firsthand how much variation can occur—30+ barrels of the same beer aged differently. Many were similar, but there were definitely differences from barrel to barrel. One in particular stood out with a completely unique and incredible acid profile. We even considered a single-barrel release before ultimately blending it.

There are also factors we simply can’t control: variability in malt and hops, differences in hop lots (which is why commercial breweries contract and select hops in person), and even how yeast is handled before it reaches your local homebrew shop. The goal isn’t to stress over these variables—but to be aware of them.

Instead, focus on what you can control. Good documentation is critical for consistency and repeatability, especially when a batch turns out significantly different—whether better or worse.

One change I made years ago was building my own grain mill to improve consistency. At the time, I was seeing significant variability in mash efficiency. If you’re relying on different shops to mill your grain, you’ll likely encounter inconsistencies—different mills, gap settings, number of passes, and even residual grain from previous batches can all affect your crush. I’ve seen cases where efficiency dropped 20% in a single batch due to a poor crush.

By milling my own grain—typically while filling the mash tun with strike water—I’ve been able to achieve much more consistent mash efficiency across batches.

In short: take good notes and standardize your process as much as possible. When you encounter outliers, your notes will help you identify what changed.

To support this, I’m updating my brew session template to capture more detail. While this likely won’t be the final version, it reflects my current setup and should help ensure I consistently record the most important variables. Below is the table I’ll be using going forward.

Session Readings
Equipment used	X
Strike water volume	X gal
Strike water temp	X °F
Mash thickness	X qt/lbs
Beginning mash pH	X
Ending mash pH	X
1st running gravity	X (1.0)
Volume into BK	X gal
Pre-Boil gravity	X (1.0)
Pre-Boil pH	X
Post-Boil gravity	X (1.0)
Post-Boil pH	X
Aeration	X l/minute
Post ferm gravity	X (1.0)
Post ferm pH	X (1.0)